How Often To Change Furnace Filters. Fiberglass filters are a lower cost option but they need to be disposed of and replaced roughly every 30 days. If your house is one that has a lot of dust youll need to change one and two-inch filters out every month four-inch filters every two months and five-inch filters every three months.
How often you need to replace the filter depends on the size of the filter. This could include dust mold pollen pet dander and a variety of other irritants. How often you would have to change the furnace filter will depend on quite a few factors starting from the thickness of the actual filter and ending with the frequency of usage of the heating.
In general the thinner the filter more often it should be replaced.
4 furnace filters should be replaced every 6-9 months. Most experts agree that the average family needs to change their furnace filter at least every ninety days. Ad Custom filters are manufactured to the exact size that you specify. A 1 to 2-inch filter should be changed every one to three months.
